Topical therapeutic preparation containing p-aminomethylbenzenesulfonamide salt and method of treating burns therewith



United States Patent i 3,497,599 TOPICAL THERAPEUTIC PREPARATION CON- TAINING p AMINOMETHYLBENZENESUL- FONAMIDE SALT AND METHOD OF TREAT- ING BURNS THEREWITH Frederick C. Nachod, Kinderhook, N.Y., assignor to Sterling Drug Inc., New York, N.Y., a corporation of Delaware N0 Drawing. Filed Mar. 18, 1966, Ser. No. 535,356 Int. Cl. A61k 27/00 US. Cl. 424-321 4 Claims ABSTRACT OF THE DISCLOSURE Composition comprising a pharmaceutically-acceptable hydrophilic base and a water-soluble salt of p-aminomethylbenzenesulfonamide with a rapidly-metabolizable, pharmaceutically-acceptable organic acid is useful for topical treatment of burn wounds of humans.

This invention relates to antibacterial compositions and to methods of treatment with said compositions.

It is an object of this invention to provide a composition and a method for topical tneatment of burn wounds of human subjects which will safely and effectively control or substantially reduce burn wound sepsis, particularly in second and third degree burns.

Burn wound infection and septicemia refractory to topical and systemic antibiotic therapy are the chief causes of death in severely burned patients, the major pathogen in many instances being Pseuaomonas aeruginosa. Parenteral antibiotics are only partially effective in the majority of cases, probably because the devascularized tissue in the area of the burn is not reached by the antibiotic. Therefore, effective topical medication which penetrates the devascularized area and burn surface is needed to suppress bacterial growth substantially.

The hydrochloride of p-aminomethylbenzenesulfonamide, a broad spectrum antibacterial agent, has been used with some success for the treatment of burns. However, the use of this compound undesirably produces a change in the acid-base balance of the patient and, specifically, it reduces significantly the carbon dioxide combining power of the blood. Significant changes in the acid-base balance cause hyperventilation as the body seeks to compensate for the imbalance, and this can be especially hazardous to patients with impaired renal or pulmonary function. In some instances, particularly when large and severe burns are involved and hence relatively large amounts of the p-aminomethylbenzenesulfonamide hydrochloride are required, hyperchloremic acidosis to a dangerous degree is produced, and other undesirable electrolyte shifts may also be produced. Under such conditions of treatment, it is normally necessary to treat the patients with supportive therapy which requires accurate monitoring of electrolytes, otherwise the hazard of over-hydration and electrolyte imbalance may occur. Therefore, only institutions which have very elaborate laboratory facilities are in a position to cope with this problem, thus limiting the use of p-aminomethylbenzensulfonamide hydrochloride.

In one aspect, the instant invention resides in the concept of a new composition of matter which is a therapeutic preparation adapted to be topically applied as a protective antibacterial mantle in the treatment of burn wounds of humans which comprises a pharmaceutically-acceptable hydrophilic base having incorporated therein in antibacterially effective amount a water-soluble salt of paminomethylbenzenesulfonamide with a rapidly-metabolizable and pharmaceutically-acceptable organic acid. In another aspect, this invention resides in the concept of ice a new method of treating burn wounds of humans which comprises applying topically to the burned area as a protective antibacterial mantle my new therapeutic preparation.

The water-soluble salt of p-aminomethylbenzenesulfonamide used in the practice of this invention is incorporated into my new therapeutic compositions in antibacterially effective amount; for the purposes of this invention the amount of the salt is approximately 5-20 percent by weight of the composition, 7-15 percent ordinarily being the preferred range. For such incorporation, the mixing and blending procedures conventional in the pharmaceutical art can be employed to distribute the p-aminornethylbenzenesulfonamide salt uniformly throughout the hydrophilic base.

The new therapeutic composition afforded by the present invention is highly effective in suppressing bacterial growth in burn wounds of humans and moreover it has the very important advantage that it can be used in relatively large quantity in the treatment of large and severe burns with minimal effect on the acid-base balance of the patient, so that little or no acidosis is produced, nor is any other major untoward response produced.

The p-aminomethylbenzenesulfonamide salts useful in the practice of this invention are generally speaking the water-soluble salts obtained by interaction of p-aminomethylbenzenesulfonamide with a suitable pharmaceutically-acceptable organic acid, the anion of which is susceptible to rapid metabolism when absorbed through the human skin into the blood stream. The acids of this type, which are well-known, are illustrated by, but not limited to, acetic acid, propion-ic acid, citric acid, isocitric acid, cis-aconitic acid, succinic acid, fuman'c acid, malic acid, and glutamic acid.

The preferred salts of the above-indicated type are those which yield aqueous solutions with pH in the approximate range 6.07.0. p-Aminomethylbenzenesulfonamide acetate is the preferred salt species.

The therapeutically-acceptable hydrophilic vase used in formulating the antibacterial preparations of this invention is a Well-known and conventional class in the pharmaceutical art. These are emusion bases, sometimes referred to as water removable ointment bases, which consist of an aqueous phase, one or more emulsifying agents, and an oleaginous phase. The aqueous phase usually forms 10-80 percent of the total base, and additional water can be incorporated if desired. A humectant, for example glycerol, propylene glycol, or a polyethylene glycol, is generally included in the aqueous phase. The oleaginous phase generally includes one or more Waxes, petrolatum, mineral oils, fats, and higher aliphatic alcohols, and the like. The emulsifiers are soaps, polyglycol esters, quaternary ammonium compounds, alkyl sulfates, alkyl aryl sulfonates, and the like. Antioxidants and preservative agents may be also added to the hydrophilic base to improve stability and shelf life.

By suitable variations of the viscosity, the new preparations of this invention can be obtained in the form of semi-solid or paste-like ointments and creams for topical application by spreading, smearing, spraying, or the like, on the area to be treated. Alternatively, and in some instances advantageously, my new therapeutic preparations can be formulated to include a suitable propellant for application from a pressurized container in the form of an aerosol.

Treatment should be started as soon as the patients burn is debrided, cleaned, and evaluated. My new thera peutic preparation is applied in amount and in frequency sufficient to provide and maintain a complete mantle for the burn wound, a layer about one-sixteenth of an inch thick applied twice daily being generally satisfactory. As treatment continues and healing progresses, the amount of the preparation required of course diminishes. Dressings are ordinarily not applied, and if used should be coarse and loose. The burn surface may be cleaned by hydrotherapy and the therapeutic preparation replaced. The duration of application generally ranges from a few days to several weeks depending on the severity of the burn, the degree of infection, and the rate of healing. Since there are no significant electrolyte changes produced, there is no necessity for close monitoring of electrolytes during the course of treatment.

By way of illustration, in second and third degree burns covering 30-40 percent of the body area of a 70 kg. patient, it is usually satisfactory to use approximately one-half pound per application, that is, a total of one pound per day, when there is applied a one-sixteenth inch layer of a pherapeutic preparation containing 10-12 percent of the p aminomethylbenzenesulfonamide salt, for instance the acetate. It will be appreciated that the amount of the therapeutic preparation used par day will vary according to the nature and site of the burn; for example, when burns in the gluteal area are involved, the preparation may be accidentally rubbed off and need replacement more often than will usually be the case when an arm burn is involved.

Although my new therapeutic preparation is particularly adapted to the treatment of burn wounds, it is also highly effective in the topical antibacterial treatment of open wounds generally, the method of application being similar to that used in treating burns.

EXAMPLES The terms part and parts in each instance indicate part or parts by weight.

p-Aminomethylbenzenesulfonamide salts The required p-aminomethylbenzenesulfonamide salts are conveniently obtained by interacting appropriate quantities of p-aminomethylbenzenesulfonamide and a suitable weak organic acid in a solvent and then isolating the salt thus produced by conventional means. This procedure is illustrated below.

One part of p aminomethylbenzenesulfonamide was dissolved in 4 parts of 95 percent ethyl alcohol by heating and stirring until a clear solution resulted at 70 C. To this solution there was added slowly, with stirring, 0.34 part of glacial acetic acid. The resulting reaction mixture was refluxed gently for one-half hour and was then cooled at 5 C. for one-half hour. The white crystalline product which separated from solution was collected on a filter, washed with cold C.) isopropyl alcohol, and then dried at 65 C. under reduced pressure. There was thus obtained 1.3 parts of p-aminomethylbenzenesulfonamide acetate as a white crystalline solid having the formula and which melted at 169172 C.

This salt was soluble in water at 25 C. to the extent of 20 percent, the pH of the 1 percent aqueous solution being 6.8.

In similar fashion, the following salts of p aminomethylbenzenesulfonamide suitable for use in practicing this invention were obtained:

Propionate, C H N O S-C H O white crystalline solid,

M.P. 157-159 C.

l-glutamate, C H N O S-C H NO white crystalline solid, M.P. l53154 C.

Succinate, (C7H10N2O2S)2'C4H6O4, while crystalline solid, M.P. 2ll 212 C.

Citrate, (C H N O S) -C H O white crystalline solid,

M.P. 159l6018l C. (dec.)

Fumarate, (CqH1 N2O2S)2"C4H4O4, white crystalline solid, M.P. 208Z10 C.

Therapeutic preparations The p-aminomethylbenzenesulfonamide salts are incorporated into pharmaceutically-acceptable hydrophilic vehicles using manipulative techniques well-known in the art. Illustrated below is the preparation of a cream containing p-aminomethylbenzenesulfonamide acetate; hydrophilic creams containing this salt represent preferred embodiments of this invention and have been found especially effective and convenient in the treatment of burn wounds of humans.

A mixture of 2.7 parts of cetyl alcohol, 9.0 parts of stearyl alcohol, and 9.0 parts of spermaceti is melted and to this melt there are added 0.03 part of n-propyl phydroxybenzoate and 0.25 part of methyl p-hydroxybenzoate. Separate aqueous solutions of 2.0 parts of polysorbate (polyoxyethylene 20 sorbitan monooleate) and of 11.6 parts of glycerol are prepared and each is warmed to the same temperature as the first solution, and then the three solutions are mixed and stirred until the resulting mixture has cooled to room temperature. To this mixture there is added a solution of 11.2 parts of paminomethylbenzenesulfonamide acetate in 16.8 parts of water containing 0.1 part of sodium bisulfite, and the mixture thus obtained is well mixed to produce a stable homogeneous cream.

The therapeutic preparations provided by this invention have been used in the manner above-indicated in treatment of first, second, and third degree burns covering 3 to 60 percent of the body surface area of humans, and in every instance have afforded safe and effective control of burn wound infection. In no case where death of the patient occurred was septicemia a primary cause of death.

Moreover, and very importantly, no significant electrolyte changes and in particular no significant changes in the acid-base balance were produced in any of the patients so treated. Particularly, the blood chloride, blood pH, and carbon dioxide combining power of the blood all remained within normal limits. Accordingly, the hazards of hyperventilation and acidosis were not encountered. There was excellent evidence in some patients that use of my new preparations had prevented the conversion of the bums from second degree burns to full thickness burns, that is, third degree; such conversion frequently occurs unless bacterial infection of the burn has been adequately controlled. In addition, because infection is controlled, small areas of epithelial cells are able to regenerate and multiply, leading to a marked decrease in need for skin grafting.

I claim:

1. A therapeutic preparation which comprises a pharmaceutically-acceptable hydrophilic base having incorpo rated therein in antibacterially effective amount a watersoluble salt of p-aminomethylbenzenesulfonamide with a rapidly-metabolizable, pharmaceutically-acceptable organic acid.

2. A therapeutic preparation in accordance with claim 1 wherein the water-soluble salt is p-aminomethylbenzenesulfonamide acetate.

3. A therapeutic cream which comprises a pharmaceutically-acceptable hydrophilic base having incorporated therein 7-15 percent by weight of p-aminomethylbenzenesulfonamide acetate.

4. The method of treating burn wounds of humans which comprises applying topically to the burned area as a protective antibacterial mantle a therapeutic preparation in accordance with claim 1.

References Cited UNITED STATES PATENTS 3,192,107 6/1965 Whitmoyer et al l6753 RICHARD L. HUFF, Primary Examiner 

